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Linux is a family of open source Unix-like operating systems based on the Linux kernel, an operating system kernel first released on September 17, 1991 by Linus Torvalds. Linux is typically packaged in a Linux distribution (or distro for short).
Distributions include the Linux kernel and supporting system software and libraries, many of which are provided by the GNU Project. Many Linux distributions use the word "Linux" in their name, but the Free Software Foundation uses the name GNU/Linux to emphasize the importance of GNU software, causing some controversy.
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Having choice is the best part of Linux, but Systemd is something so ubiquitous to Linux that it might as well be called Systemd/Linux instead of GNU/Linux.
When you think of it like that, it feels much less like a bloated behemoth that needs to be de-monopolised and more like an integral piece of the puzzle that is turning the Linux kernel into an functional operating system.
systems always implies Linux, but Linux doesn't necessarily imply systemd.
I always try to cover most of my stack with systemd components because they actually tend to be quite sane with a very transparent configuration. It's no surprise a lot of distributions picked it up. As you said, it does exactly that, make an OS based on Linux easily available. Sure you can do the same with a variety of other tools, but just letting systemd do the heavy lifting for you sure is tempting.
That doesn't mean it's the only choice. I'd love to try Chimera Linux one day which doesn't include systemd (in fact it doesn't include a lot of stuff most other distributions do) but it ticks a lot of boxes for many.
All of this shit packed in is why it sucks. Do one thing and do it well. Try setting up a script to run on boot that doesn't stop executing until you want to turn your pc off and watch all traces of sanity drain from your being. Now try it on freebsd. Much much easier
What's the problem with that script? That's such a basic use case and not very hard to do at all in systemd.
Where do you struggle with it? Can we maybe help with something?
systemd is great, but being disingenious isn't helping anyone:
chrony -> sd-timesyncd [...] one less daemon
just because it ships with systemd doesn't mean it magically runs without it's own process
Do we have to bring this up again? It's just boring.
systemd is here and it isn't going anywhere soon. It's an improvement over SysV, but the core init system is arguably less well-designed than some of the other options that were on the table 10 years ago when its adoption started. The systemd userspace ecosystem has significantly stifled development of alternatives that provide equivalent functionality, which has led to less experimentation and innovation in those areas. In many cases those systemd add-on services provide less functionality than what they have replaced, but are adopted simply because they are part of the systemd ecosystem. The core unit file format is verbose and somewhat awkward, and the *ctl utilities are messy and sometimes unfriendly.
Like most Red Hat-originated software written in the last 15 years, it valiantly attempts to solve real problems with Linux, and mostly achieves that, but there are enough corner cases and short-sighted design decisions that it ends up being mediocre and somewhat annoying.
Personally I hope that someone comes along and takes the lessons learned and rewrites it, much like Pulseaudio has been replaced by Pipewire. Perhaps if someone decides it needs rewriting in Rust?
Thanks for summarizing my feelings on systemd in a less inflammatory way than if I had written it myself.
I've found that most distributions have implemented it properly and for the most part it works quite well and stays out of my way, it's only when for some reason you have to dive into the minutiae of a unit file and getting into all the dependencies and stuff that it gets annoying quickly.
The dependency system takes a bit to understand but compared to like upstart it was a massive improvement.
Everybody gangsta until A start job is running for ... (10s / 1min 30s)
I don't see how exactly that is systemd's fault.
You are blaming it for having proper dependency handling?
I'm blaming it for making it a pain in the ass to debug dependency problems and for having the confusing, non-intuitive, overly verbose and redundant syntax that probably caused the problem in the first place.
Like, who the hell can memorize all the subtle differences in behavior between After=, Requires=, Wants=, Requisite=, BindsTo=, PartOf=, UpHolds= and then all their "reverse" equivalents?
You're right that the difference isn't overly obvious. However, for most services, Wants= is enough. I think some of these (like Requisite=) came from actual users' demands where they had to solve corner cases in their setup that systemd did not allow with the existing features. I think especially UpheldBy= is a smart addition; it adds restarting to a service only if that services is used as a dependency for the one it upholds.
Finally a systemd praise post after so many hateful remarks. I knew systemd could do dns resolving but just learned it could handle the entire network stack and replace NetworkManager. I have a question: How can services such as Apache adapt to both NM and systemd at the same time? NM and systemd have different wait-online services. You can also add systemd-analyze for boot time analysis to the list.
How can services such as Apache adapt to both NM and systemd at the same time? NM and systemd have different wait-online services
If you look at the systemd unit for Apache you'll just find After=network.target - it doesn't wait-online at all. Apache doesn't really care if you're using NM or systemd-networkd, it simply queries the system (like the ip command does) to know what's going on with the network. It was designed as recommended for moderns programs: it is aware that your network might change and listens for the appropriate signals and takes care of the binds dynamically.
I knew systemd could do dns resolving but just learned it could handle the entire network stack and replace NetworkManager.
It depends on your use case. I have three machines and use NetworkManager on one of them and systemd-networkd on the others. The latter is great for static configurations, but for a notebook that roams WiFi networks, it doesn't make the most sense.